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// Copyright (c) 2018 The OTS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "avar.h"
#include "fvar.h"
#include "variations.h"
namespace ots {
// -----------------------------------------------------------------------------
// OpenTypeAVAR
// -----------------------------------------------------------------------------
bool OpenTypeAVAR::Parse(const uint8_t* data, size_t length) {
Buffer table(data, length);
if (!table.ReadU16(&this->majorVersion) ||
!table.ReadU16(&this->minorVersion) ||
!table.ReadU16(&this->reserved) ||
!table.ReadU16(&this->axisCount)) {
return Drop("Failed to read table header");
}
if (this->majorVersion > 2) {
return Drop("Unknown table version");
}
if (this->majorVersion == 1) {
// We can fix table
if (this->minorVersion > 0) {
// we only know how to serialize version 1.0
Warning("Downgrading minor version to 0");
this->minorVersion = 0;
}
if (this->reserved != 0) {
Warning("Expected reserved=0");
this->reserved = 0;
}
} else {
// We serialize data unchanged, so drop even for minor errors
if (this->minorVersion > 0) {
return Drop("Unknown minor table version");
}
if (this->reserved != 0) {
return Drop("Expected reserved=0");
}
}
OpenTypeFVAR* fvar = static_cast<OpenTypeFVAR*>(
GetFont()->GetTypedTable(OTS_TAG_FVAR));
if (!fvar) {
return DropVariations("Required fvar table is missing");
}
if (axisCount != fvar->AxisCount()) {
return Drop("Axis count mismatch");
}
for (size_t i = 0; i < this->axisCount; i++) {
this->axisSegmentMaps.emplace_back();
uint16_t positionMapCount;
if (!table.ReadU16(&positionMapCount)) {
return Drop("Failed to read position map count");
}
int foundRequiredMappings = 0;
for (size_t j = 0; j < positionMapCount; j++) {
AxisValueMap map;
if (!table.ReadS16(&map.fromCoordinate) ||
!table.ReadS16(&map.toCoordinate)) {
return Drop("Failed to read axis value map");
}
if (map.fromCoordinate < -0x4000 ||
map.fromCoordinate > 0x4000 ||
map.toCoordinate < -0x4000 ||
map.toCoordinate > 0x4000) {
return Drop("Axis value map coordinate out of range");
}
if (j > 0) {
if (map.fromCoordinate <= this->axisSegmentMaps[i].back().fromCoordinate ||
map.toCoordinate < this->axisSegmentMaps[i].back().toCoordinate) {
return Drop("Axis value map out of order");
}
}
if ((map.fromCoordinate == -0x4000 && map.toCoordinate == -0x4000) ||
(map.fromCoordinate == 0 && map.toCoordinate == 0) ||
(map.fromCoordinate == 0x4000 && map.toCoordinate == 0x4000)) {
++foundRequiredMappings;
}
this->axisSegmentMaps[i].push_back(map);
}
if (positionMapCount > 0 && foundRequiredMappings != 3) {
return Drop("A required mapping (for -1, 0 or 1) is missing");
}
}
if (this->majorVersion < 2)
return true;
uint32_t axisIndexMapOffset;
uint32_t varStoreOffset;
if (!table.ReadU32(&axisIndexMapOffset) ||
!table.ReadU32(&varStoreOffset)) {
return Drop("Failed to read version 2 offsets");
}
Font *font = GetFont();
uint32_t headerSize = table.offset();
if (axisIndexMapOffset) {
if (axisIndexMapOffset < headerSize || axisIndexMapOffset >= length) {
return Drop("Bad delta set index offset in table header");
}
if (!ParseDeltaSetIndexMap(font, data + axisIndexMapOffset, length - axisIndexMapOffset)) {
return Drop("Failed to parse delta set index map");
}
}
if (varStoreOffset) {
if (varStoreOffset < headerSize || varStoreOffset >= length) {
return Drop("Bad item variation store offset in table header");
}
if (!ParseItemVariationStore(font, data + varStoreOffset, length - varStoreOffset)) {
return Drop("Failed to parse item variation store");
}
}
this->m_data = data;
this->m_length = length;
return true;
}
bool OpenTypeAVAR::Serialize(OTSStream* out) {
if (this->majorVersion >= 2) {
if (!out->Write(this->m_data, this->m_length)) {
return Error("Failed to write table");
}
return true;
}
if (!out->WriteU16(this->majorVersion) ||
!out->WriteU16(this->minorVersion) ||
!out->WriteU16(this->reserved) ||
!out->WriteU16(this->axisCount)) {
return Error("Failed to write table");
}
for (size_t i = 0; i < this->axisCount; i++) {
const auto& axisValueMap = this->axisSegmentMaps[i];
if (!out->WriteU16(axisValueMap.size())) {
return Error("Failed to write table");
}
for (size_t j = 0; j < axisValueMap.size(); j++) {
if (!out->WriteS16(axisValueMap[j].fromCoordinate) ||
!out->WriteS16(axisValueMap[j].toCoordinate)) {
return Error("Failed to write table");
}
}
}
return true;
}
} // namespace ots